JP2504572B2 - Drainage method using underdrain drainage pipe and underdrain drainage pipe used for the method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an underground drainage pipe buried underground in a place where drainage of underground water is required, such as a bunker or fairway of a golf course, or a wetland. The present invention relates to a discharge method for discharging underground water to a desired drainage point, and an underdrain drainage pipe used therefor.

[Conventional technology]

As the underdrain drainage pipe of this type, the ones having the structures shown in [1] and [2] below have been conventionally known.

[1] The pipe peripheral wall is composed of a mesh-like cylindrical body, and is configured so as to allow the entry of underground water into the pipe from the entire circumference of the pipe peripheral wall.

[2] As shown in FIG. 6, the pipe main body (21) is largely cut out over its entire length, and the rectangular gutter (22) is arranged inside the pipe main body (21), and the pipe main body is connected by the connecting portion (23). It is integrally connected to (21) and the fluid inlet (24) is provided between the pipe body (21) and the gutter (22).
And the underground drainage pipe that is configured to cause the underground water rising in the fluid inlet (24) to flow into the gutter (22) by overflow, the inlet of the fluid inlet (24) faces downward. It is buried in the ground in such a state that the groundwater is drained by the gutter (22) while suppressing the clogging of the fluid inlet (24) with the sand and the inflow of sand into the gutter (22). It was made to flow to the location (see Japanese Utility Model Laid-Open No. 51-155505).

[3] The lower part of the tubular pipe body is bent upward to form a pumping section, and a drainage hole communicating with the pipe body is formed in the upper part of the pumping section, and on the outer surface of the side wall below the drainage hole. One provided with a sand blocking part that projects in a substantially horizontal direction (Actual exploitation: 61-58229
(See the official gazette).

[Problems to be Solved by the Invention]

However, in the conventional means described above in [1], if the mesh is made small, the infiltration of underground water is hindered and the effect of the drainage pipe is not obtained. Sediment invades with the intermediate water, and this deposits and deposits, which hinders drainage.

In addition, in the structure shown in the above [2], the above [1]
Although it is possible to avoid the intrusion of earth and sand from above through the mesh as in the case of (3), there are problems as described in (a) to (c) below.

(A) Since the lower part of the pipe body (21) is notched over the entire length, the strength against the sediment pressure on the lateral outer surface of the pipe body (21) is extremely low, and in a short period of time,
The tube body (21) is destroyed, or the tube body (21)
The lower end side (21a) of the gutter (22) approaches or abuts,
There was a great risk that the drainage condition would deteriorate significantly, and there was a defect in durability.

(B) Especially, the shape of the fluid inlet (24) is such that the upper and lower intermediate parts are wider than the inlet, so it is not possible to sufficiently prevent the inflow of earth and sand into the gutter (22), which is an early stage. The gutter (22) was clogged and the drainage function deteriorated significantly. That is,
The earth and sand that have entered the fluid inlet (24) are not fixed because of the shape of the fluid inlet (24), but are easily floated by the rising water, and the underground water is introduced. Mouth (2
When the rising velocity in 4) increases, not only fine earth and sand but also relatively large stones and sand flow with groundwater into the gutter (22), and flow with groundwater from a distant location. This is because the fine sediment that has flowed into the gutter (22) is not filtered by the sediment near the fluid inlet (24).

(C) Since the shape of the fluid inlet (24) is wider at the upper and lower intermediate portions than the inlet, the space occupied by the fluid inlet (24) is very large and the gutter (22) is cut off. The cross-sectional area of the pipe body (21) is large relative to the area, and the bulk of the pipe is large.
Therefore, not only the material cost becomes high, but also a large groove has to be excavated for burying in the ground, which is disadvantageous in that it requires a lot of cost and labor for construction.

Further, in the structure shown in [3] above, as in the cases of [1] and [2] above, intrusion of earth and sand from above, entrainment and inflow of large earth and sand into the fluid inlet, or the entire pipe Although bulkiness can be avoided, there are problems as described in (d) and (e) below.

(D) The upwardly recessed pumping section formed in the lower part of the pipe body ensures that the sediment blocking section consisting of a large number of resistors acts on the sediment in the underground water rising in the pumping section. As described above, since the pumping section has an extremely deep depth with respect to the pipe diameter, it is difficult to provide sufficient strength against pressure from the inside to the outside of the pumping section.

(E) Since the pumping section is deep and the side wall of the pumping section is a steep slope approximately along the vertical line, even if this pipe body is pressed downward, the sediment inside the pumping section will not It does not receive much strong compression from the side. Therefore, as for the sediment in the pumping section, even if the large one is restricted from rising due to the action of the sediment blocking section, the smaller one is carried along with the rising water in the pumping section to the fluid inlet side. Tend.

An object of the present invention is to sufficiently prevent clogging by sediment of the underground water inflow port and inflow of sediment into the pipe, and yet to have sufficient strength against external pressure due to sediment, especially for a long period of time. The point is to ensure that a good drainage function can be exerted, and also that construction work can be carried out inexpensively and quickly.

[Means for solving the problem]

The technical means which is a feature of the method of the present invention taken to achieve the above-mentioned object is a part of the peripheral wall of the pipe main body, which is narrower in the inner side and narrower in the inner side than the inlet side, and the opening ends of the inlet. And the innermost position of the imaginary triangle are formed so that the apex angle is approximately a right angle or more, and a recessed portion is formed along the pipe axis direction, and this pipe main body has a cross-sectional shape. Part of the peripheral wall of the pipe is formed into a closed loop shape that is recessed inward of the pipe,
At the inner position of the recessed portion of the narrowed portion, an upstream water inlet formed by a through hole that penetrates the peripheral wall of the pipe and communicates the inside and outside of the pipe is formed, and the inlet portion of the recessed portion is more than the upstream water inlet. A culvert drainage pipe provided with a gutter-shaped drainage flow path portion along the pipe axis direction at a position near the bottom is buried in the ground in a posture in which the inlet side of the recessed portion is located below the upstream water inlet,
After raising underground water to the inner depth side of the recessed portion, it is caused to flow into the pipe main body from the upstream water inlet, and the inflowing underground water is caused to flow to a drainage point through the inside of the pipe main body. That's what I did.

In addition, for the same purpose, in constructing the underdrain drainage pipe, a part of the pipe peripheral wall of the pipe body has a narrowed shape that becomes narrower toward the inner side than the entrance side, and both ends of the entrance opening and the innermost position. A concave part is formed along the pipe axis direction so that the apex angle of the virtual triangle that connects to Is formed in a closed loop shape that is recessed toward the inside of the pipe, and an upstream water inlet formed by a through hole that penetrates the peripheral wall of the pipe and communicates with the inside and outside of the pipe is formed at the inner position of the recessed portion that is narrowed inward. With
It is preferable to provide a gutter-shaped drainage flow path portion along the pipe axis direction at a position closer to the inlet side of the recess than the upstream water inlet.

As the underdrain drainage pipe, in the pipe main body, the drainage flow path portions are formed on both sides of the recessed portion, and the drainage flow passage portion formed in a deep and narrow shape opposite to the recessed portion may be used. Good.

[Work]

The effect of taking the above technical means is as follows.

That is, underground water such as rainwater that has infiltrated the ground above the lower end of the pipe body reaches the recessed space below the recessed part through the lower side of the pipe main body, and the water level in the recessed space is After rising, it flows up into the pipe from the upstream water inlet.

b. According to the present invention, the recessed part space formed by the recessed part of the recessed part has a narrowed shape that becomes narrower toward the rear side than the entrance side, and both ends of the opening of the entrance and the innermost position. Since the apex angle of the virtual triangle that connects the two is formed to be larger than the right angle, the gentle sloping surface formed on the inner surface of the recess allows the sand pressing action to reach the deepest part of the recess. It is configured to work easily. For this reason,
For example, compared with a structure in which this apex angle is configured to be an acute angle and the entrance is restricted by narrowing the entrance, the earth and sand that enter the recessed space will be mutually affected by the pressure of the earth and sand from above and below. It is pressed against each other and compacted, and the earth and sand in the recessed space becomes relatively hard to move. Therefore, in this state, the earth and sand in the recessed space itself act as a filter against the earth and sand that is about to flow in from the outside, and limit the entrainment of earth and sand to the underground water to the upstream water inlet as much as possible. Become. In other words, by widening the opening width of the recessed part, it is possible to effectively consolidate the sediment in this recessed part space, and the sediment itself has a filter function so that groundwater in the natural world is purified in the sediment. It has a.

c. Moreover, the migration of sediment from the recessed space through the water inlet is double blocked by resisting gravity and adding passage resistance as an orifice of the upstream water inlet,
The flow of underground water in the upwelling state that passes through the upstream water inlet is almost free of sediment.

d. Further, in the present invention, since the pipe main body is constituted by the strength structure of the pipe peripheral wall of the closed loop over substantially the entire circumference, it can be formed in a shape that is strong against external pressure due to earth and sand,
It is possible to suppress the deformation and damage of the pipe body due to the external pressure due to the earth and sand, and to exert a good drainage function for a long period of time.

e. Furthermore, inside the drainage pipe, there is a fluid discharge part at a position outside the upstream water inlet where the underground water springs up, and the flow of underground water at the fluid discharge part is from the upstream water inlet. Since there is no flow resistance due to the underground water flowing in, the flow velocity is not reduced, and it is easy to cause contaminants such as fine earth and sand to flow down to the lower side of the flow path.

〔The invention's effect〕

 The effects of the above configuration are as follows.

I. The drainage function deterioration due to clogging at the upstream water inlet and the inflow of sediment into the pipe is defined as the inflow of underground water into the drain pipe due to the upwelling of water, and gravity is applied to the uplifted sediment. And the upstream water inlet serves as a passage resistance as an orifice, and can be strongly suppressed by synergistic use with compacted earth and sand like a filter in the recessed space. Moreover, the good drainage function is ensured for a long period of time, because the pipe body is composed of a strength structure with a closed loop pipe peripheral wall, so there is no risk of deterioration due to deformation or damage of the pipe body due to external pressure due to earth and sand. Can be maintained.

B. Moreover, since the fluid flow at the fluid discharge portion flows down without receiving the resistance of the infiltration water into the pipe, the gradient at the time of laying the drain pipe can be extremely gentle. In other words,
There is no need to dig deep into the ditch to give the drain a large slope. Therefore, the construction work of the drainage pipe can be easily performed at low cost, and the drainage method using the underdrain drainage pipe, which is more excellent in terms of drainage performance and durability and workability of the drainage pipe, was established.

C. Moreover, by configuring as described in claim 2,
Above a. It is now possible to provide an underdrain drainage pipe that is advantageous for carrying out the excellent drainage method of.

D. In particular, when the drainage flow path portion is formed into a narrowed shape as described in claim 3, the effect of the sediment flowing by the running water in the drainage flow path portion can be increased relative to the amount of water, and the sedimentation and sedimentation of the sediment in the pipe is further effective. Can be prevented.

〔Example〕

 Next, an embodiment will be described with reference to FIGS. 1 and 2.

Attach the tube peripheral wall (2A) of the tube body (2) made of synthetic resin,
The curved plates (11), (12), and (13) that are smoothly continuous form a substantially continuous shape over the entire circumference.

The curved plates (11) and (12) are made of a non-water-permeable material,
Sediment is prevented from entering the pipe.

The curved plate (13) is provided with a recessed portion (10) which is recessed inward of the pipe, and the recessed portion space having a narrowed shape is formed in the recessed portion (1).
0) is formed on one side of the tube body (2).

The recessed part (10) has a narrowed shape in which a part of the peripheral wall (2A) of the pipe main body (2) becomes narrower toward the inner side than the inlet side, and both ends of the opening of the inlet and the innermost position. The imaginary triangles connecting the two are formed along the pipe axial direction by being recessed so that the apex angle becomes an angle larger than a right angle, and the pipe main body (2) has a sectional shape and a peripheral wall (2A ) Is a closed rape shape with a part recessed inward of the pipe.

In the recessed part (10), a position (16) deeper than the entrance part (17) of the recessed part space, preferably near the deepest part, is provided with an upstream water inlet (14) consisting of a through hole communicating the inside and outside of the pipe. In a state of being intermittently positioned in the length direction of the pipe body (2), that is,
It is formed in an appropriate size and dispersed.

A drainage flow channel (15) is formed on the inner bottom of the pipe body (2) at a position deviated from the upstream water inlet (14), that is, on both sides of the recessed space, and the drainage flow channel ( 15) is formed in a narrowed shape that faces away from the recessed space.

In short, the underdrain drainage pipe, as shown in FIG.
The recessed portion space is inclined downward and buried in the sand (4) in a wetland or the like in a golf course,
A good drainage function is surely demonstrated for a long time as follows.

(A) Underground water (5) such as rainwater that has infiltrated from the ground surface (1)
Since the curved plates (11) and (12) are impermeable to water, they flow into the recessed space through the lower side of the pipe body (2) and rise in the recessed space, after which the upstream water inlet. The underground water (5) flowing into the pipe from the (14) in a state of rising, and then flowing into the pipe, the underground water (5) flows down to the drainage flow path part (15) and then the one end side of the pipe in the drainage flow path part (15). It flows to and is taken out from the ground to the desired drainage point.

(B) When the underground water (5) rises in the recessed space, the flow velocity of the underground water (5) decreases due to the resistance of the sediment in the recessed space, and the sediment sediments by its own weight. It is possible to sufficiently prevent the sediment from flowing along with the ascending groundwater (5) and flowing into the pipe from the upstream water inlet (14).

(C) The earth and sand in the recessed space having a narrowed shape is clamped by the pressure (P) of the earth and sand from below to make it impossible to move relatively, and the earth and sand that has flowed from another place is tightened in the recessed space. It is stopped by the filtering action of the collected sediment, and as a whole, the inflow of sediment into the pipe can be very effectively prevented.

(D) Even if fine sediment flows into the pipe, underground water can be made to flow by increasing the flow velocity for the amount of water in the narrowed drainage flow path (15). It is possible to reliably prevent clogging due to sedimentation and sedimentation, and to smoothly and reliably discharge sediment that has entered the pipe.

[Another embodiment]

 Next, another embodiment will be described.

The present invention is not limited to the above embodiments, and the following configuration changes can be made, for example.

The cross-sectional size and cross-sectional shape of the pipe body (2) can be appropriately changed. For example, as shown in FIGS. 3 and 4, the non-water-permeable plate portions (11) and (12) are formed in a flat shape. May be the fourth
The recessed portion (10) may be formed by bending as shown in the figure, or a plurality of recessed portions (10) may be formed as shown in FIG.

The upstream water inlet (14) can be appropriately set in terms of shape, diameter, installation density and the like.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention, FIG. 1 is an explanatory view of the underground drainage pipe in an embedded state, and FIG. 2 is a sectional view of the underdrain drainage pipe. 3 to 5 are cross-sectional views showing different embodiments of the present invention. FIG. 6 is a sectional view of a conventional example. (2) …… Pipe body, (2A) …… Pipe peripheral wall, (10) …… Recessed part, (14) …… Upstream water inlet, (15) …… Drainage flow path part,
(16) …… Deep position, (17) …… Inlet.

Claims (3)

(57) [Claims] 1. A hypothetical shape connecting a part of a peripheral wall (2A) of a main pipe body (2A) to a deeper side than an entrance side and connecting both ends of the opening of the entrance to the innermost position. A recessed portion (10) which is recessed so that the apex angle of the triangle is substantially equal to or larger than a right angle is formed along the pipe axial direction, and the pipe body (2) has a cross-sectional shape along the pipe peripheral wall ( Part of 2A) is formed into a closed loop shape that is recessed inward of the pipe, and the recessed part (1
At the back position (16) of (0), the upstream water inlet (1) is formed by a through hole that penetrates the pipe peripheral wall (2A) and connects the inside and outside of the pipe.
4) is formed, and a gutter-shaped drainage flow path part (15) along the pipe axis direction is provided at a position closer to the inlet part (17) of the recessed part (10) than the upstream water inlet (14). A certain underdrain drainage pipe is buried in the ground with the inlet (17) side of the recessed part (10) positioned below the upflow inlet (14), and underground water is buried in the recessed part (10). After being raised to the inner side of the pipe, it is made to flow into the pipe body (2) from the upstream water inlet (14), and the underground water that has flowed into the pipe body (2) is discharged to a drainage point. A drainage method using a flowing underdrain pipe. 2. A part of the peripheral wall (2A) of the pipe body (2), which has a narrowed shape that is narrower toward the inner side than the inlet side, and which connects the opening ends of the inlet and the innermost position. A recessed portion (10) which is recessed so that the apex angle of the triangle is substantially equal to or larger than a right angle is formed along the pipe axial direction, and the pipe body (2) has a cross-sectional shape along the pipe peripheral wall ( Part of 2A) is formed into a closed loop shape that is recessed toward the inside of the pipe, and the inner part of the recess (10) in the narrowed part penetrates the peripheral wall (2A) to communicate the inside and outside of the pipe. The upstream water inlet port (14) formed by the through hole, and along the pipe axis direction at a position closer to the inlet (17) side of the recessed portion (10) than the upstream water inlet port (14). An underdrain drainage pipe with a gutter-shaped drainage channel (15). 3. The drainage flow channel (15) is formed on both sides of the recess (10) in the pipe body (2), and
The underdrain drainage pipe according to claim 2, wherein the underdrain drainage pipe is formed in a narrowed shape in a direction opposite to the recessed portion (10).